Beson



3 Sheets-Sheet 1..

(No Model.)

C. WEATHERSON.

AIR HOIST.

Patented Deo. l5, 1891.

MMMMMMMMMMMMMM 3 Sheets-Sheet 2.

(No Model.)

C. WE'ATHERSON. AIR Hols'r.

Patented Dec. `15, 1891.

we Ncnms wens co., vnoromrum waswmamn, n. c.

( NNNNNNNN 10.465,008. Patented Dec. 15,1891..

Hill

NTTED STATES PATENT OFFICE.

CHRISTOPHER WEATI-IERSON, OF CIIICAGO, ILLINOIS, ASSIGNOR TO HIMSELF AND THE CHICAGO FORGE AND BOLT COMPANY, OE SAME PLACE.

A l R H O l S T SPECIFICATION forming part of Letters Patent No. 465,008, dated December 15, 1891.

Application filed May 27, 1889. Serial No. 312,242. (No model.)

To @ZZ whom t may concern:

Be it known that I, CHRISTOPHER WEATH- ERSON, a citizen of the United States, residing at Chicago, Illinois, have invented certain new and useful Improvements in Air- Hoists, of which the following is a specification.

This invention relates to a hoist in which air under pressure is admitted to a power-cyl inder havinga reciprocating piston therein and a pistonrod projected beyond the cylinder-head to aord means for attaching the load to be moved. The supply and exhaust of air are controlled by suitable valves, and in the particular construction shown the air is admitted through a supply-pipe having a three-way valve therein, and a lever is connected to the valve-stem, so that the latter may be turned in its three positions in order to hoist the load, to hold it suspended, and to lower it.

The invention consists in the constructional features.

In the drawings, Figure l is a side elevation of the device, a sectionthereof removed. Fig. 2 is a vertical section through the powercylinder and supply-pipe. Fig. 3 is a front view of the hoisting-lever and showing' the valve-passages in dotted lines; and Fig. 4 is a cross-section through the valve-casing, the valve showing in side elevation. Fig. 5 is a vertical sectional elevation through the val ve.

A represents the cylinder, which will be proportioned to the amount of power required. W'hen it is designed to use the hoist for transporting loads along a Way, the upper cylinder-head may have the integral lugs a a to support the attaching-bolt A. The piston is preferably constructed in two longitudinal sections B B, and a leather gasket l) is inserted between the sections, an edge D ofthe gasket being turned down between thecdge of the section B and the wall of the cylinder. This edge o is beveled, and a beveled channel a' is formed in the inner face of the head to receive the packing without injury thereto.

In order to keep the piston packed, I form the annular chamber C in the periphery of section B and provide slots c, communicating with the interior of the chamber, whereby air is admitted into the annular chamber and the packing is forced into contact with the cylinder-wall- In order to admit atmospheric air into the cylinder above the piston, the former is provided at a suitable distance from its upper end with apertures d, through which the air enters freely during the downward movement of,l the piston and escapes freely during its upward movementuntil the piston cuts on' 6c the escape by covering the apertures. The air which is thus prevented from escape forms a cushion to the piston at the limit of its upward stroke and prevents jarring or shock.

C is the piston-rod, the end of which outside the cylinder may be provided with a hook to adapt it to engage the load.

D is the supply-pipe, through which air under pressure will be forced.

E is the valve-casing, into which the supply-pipe D is screwed. This casing is bored to form a seat for the valve F, the latter being of the conical-plug type and having the aperturefand the stem F.

E is a passage through the casing E, one end of said passage communicating with the supply-pipe and the other with a passage G, formed in thecylinder-head and opening into the cylinder. The passage E has a branch V8o e', which terminates at the valve-seat, and opposite the mouth of this passage another e2, which delivers into the outer atmosphere.

Instead of the three-way valve above described, it is evident that a simple valve may 85 be used to control the admission of the air to the cylinder and a separate exhaust may be used; but I prefer the construction shown, inasmuch as it simplifies the operation, only oneoperating-lever being necessary to secure 9o both movements ofthe piston.

II is the operating-lever, which is keyed 011 the valve-stem and confined by a springwasher Z', held by the nut 1i on the threaded end of the stem, whereby the valve is held 95 tightly to its seat I is a guide, which may be the continuous flange of the valve-casing, as shown in Figs.

2 and 4, or said flange may be segmental, as shown in Figs. 1 and 3. The lever is prefer- :oc`

ably secured to the valve-stem in such manner that one of its ends shall project sopas to ride upon the guide I, and the latteris provided with a locking-notch i', which is adapted to receive a suitable locking projection on the end of the lever, so that When the lever is brought to a horizontal position it is locked by the pressure of the spring-Washer, the resiliency of which permits the lever to be freed bya slight outward pull. Will preferably be so secured to the valvestem that at the limitof the movement of the lever the valve-aperture registers with passage E and the air is permitted to enter the cylinder and cause the movement of the piston to lift the load. The lever being brought to a horizontal position, the further supply of air is cut off, but the piston is held at its upward limit and the load suspended. If the hoist be used to move the load along a Way, the air-supply pipe may be flexible to permit of said movement. Then it is desired to This lever hold the valve closely to its seat, I provide an air-chamber .l at the base of the Valve, Which may be conveniently done by hollowing out the casing and tting into threads in theWall of the cut-away portion a screw-plug, as K. An aperturel is made in the'casing to permit air to pass into the chamber at the base of the valve, and thereby the latter is held closely to its seat and all leakage prevented.

This hoist may be usedeither as a stationary or as a movable hoist and for all purposes to which such devices are commonly applied.

I claim- In an air-hoist, the combination o f the power-cylinder and a pipe for supplying air under pressure thereto, la valve 2located in said pipe, an operating-handle secured to the stem ot' the valve, a guide or bearing for said handle having thereon a locking-notch, and a locking projection on the handle adapted to enter said notch, and a spring secured against the lever to permit the locking and unlocking thereof, substantially as described. 5o

CHRISTOPHER WEATHERSON. Vitnesses:

FRANK NEWELL,

O. C. LINTHICUM. 

